Ignition system and cut-off



P 1939- I B. L. MATTHEWS El AL 2,155,976

IGNITION SYSTEM AND CUT-OFF Filed Jan. 10, 1935 if t I "in II 4/6 I2 INVENTbR 4AM 2f M.

BY 1 7H Patented Apr. 25, 1939 IGNITION SYSTEM AND CUT-OFF Birchard L. Matthews, Iakewood, and John '1'. Marvin, Falrview Village, Ohio, assignors to The Patrol Valve Company, Cleveland, Ohio Applicatifin January 10, 1935, Serial No.1,194

11 Claims.

This invention relates to a device for ignition of a fuel burner. The device is designed to provide an igniter having a pilot designed to burn constantly, and actuating means toignite the fuel burner, with means to prevent ignition of the said burner if the pilot is not ignited. In other words, means is provided to cut oil, or maintain cut off, the supply of fuel to said burner in case the constant pilot is extinguished.

Further provision is made to cut off the flow of fuel to the constant pilot in case it becomes extinguished. Releasable means is provided for readily opening the constant pilot line'for relighting. Provision is likewise made to maintain the supply of fuel to the constant pilot once it is ignited.

A runner arm is provided, that conveys flame from the constant pilot to an-ignition pilot, at the same time assisting in the ignition of the burner, and ultimately conveying the flame to a control in the supply of fuel to the main burner. The ignition pilot is supplied with fuel independently of this last control.

It is an object of this invention to provide a control of this type having a constant pilot,

with means to cut oif the supply of fuel thereto if the pilot is extinguished.

Another object is to provide an auxiliary burner lgnitable by said constant pilot, and means operable thereby to keep the pilot fuel line open.

A further object is to design said last means to cut off the fuel supply to the auxiliaryburner upon its extinguishment.

A further object is to design the control to open quickly by a large supply of fuel thereto, and then automatically reduce said supply whereby to save fuel.

Another object is to provide a normally extinguished ignition pilot, ignitable only when 40 the constant pilot is burning.

Another object is to provide a normally extinguished ignition pilot, remote from said constant pilot, and a means to convey the flame of the constant pilot to theignition pilot. 45, Another object is to use the-said conveying means as a joint means to ignite the main burner; or as a sole means without the pilot.

Another object'is to admit fuel to said conveying means only when the constant pilot is ignited. Another object is to provide meansresponsive to the ignition of the conveying means to open the main burner gas supply. Another object is to provide means responsive to ignition of said conveying means to open the main burner supply, said first means operating only when the conveying of the flame extends the complete length of the conveying means.

Another object is to provide means to reduce the quantity of'fuel to the conveying means when the main burner is ignited. 5

Another object is to provide a lighter having the constant pilot and a control flame, both outside the oven, with means for conveying the flame into the oven for igniting the burner therein. 10

Another object is to provide a unitary valve structure containing the control valves in compact assembly.

Another object is to provide a normally open pilot valve combined in a unitary structure with 15 a main line control valve dependent in its operation upon the status of the pilot valve.

It will be observed that the device is described as applicable to a gas range oven. It is to be understood that it is of broader applicability, 20 not being limited to a gas range, or to the 'use of a gaseous fuel. It will operate with any fluid fuel. Further, its principles are applicable to other-than fluid fuels. These explanations should be understood in the following description and 5 claims.

Fig. 1 is an elevation of the device with parts shown in section.

Fig. 2 is a section on the line 2-2 of Fig. 1 showing the runner arm. 30 Fig. 3 is a section on the line 3-3 of Fig. 2

showing the igniting pilot.

In the device an oven burner is indicated at Ill. The oven is shown in fragment at H, the

lateral vertical wall thereof appearing at l2, in 5 Fig. 2 and. Fig. 3. t

In the control mechanism the gas manifold is indicated at It and the main gas cock attached thereto is indicated at M. Two bleed lines l5 and I6 lead from manifold IS. The 40 main gas line fromthe gas cock leads off at IT to a T l8 where it'is divided, one branch' I! leading into section B of the control valve generally indicated at 20. The other branch from T l8 leads, as at 2|, into the'back section C 45 of the valve.

Line i6 is controlled by a push button spring operated valve 22. This line leads to a T 23 where it divides, one section going into section A of valve 20 by means of'line- 24. The other '50 section from T 23 leads through line 25 to a mixing valve 26 and thence to operating burner 21a. I i

Line l5 leads into chamber 21 0! section A of valve 20. Outlet from this chamber is controlled. 55

- tion A of valve 26 leads to a mixing valve 35 and thence to a constant pilot 36. i

Section B of the valve includes a valve stem 31!: having thereon a valve head 38b engageable against valve seat 33b or'valve seat 46b. The stem 3'": has a grooved passageflb therein, providing communication between passageway 32' and outlet line 42, that leads to mixing valve 43 and.- thence to' second operating pilot 44b. Valve head 38b likewisecontrols the flow of gas to main line 45 that leads through a thermostat 46 thence back to a mixer 41 and to main burner ID. A bi-metal element 48b controlled by control burner 44b operates valve stem 31b. -A by pass 49 leads from passage 32 within the valve to a mix- 'ing valve 50 andthence to extension line 62 shown in Figs. 2 and 3 to ignition pilot '53 located at some point adjacent burner I6. The device may be mounted ona pedestal 54 I and support 55 the latter being secured to the outside of the oven. Burners 21a, 36, 44b and 53, are all directly or indirectly mounted on support 55.

Extending through an opening in oven wall i2 is a runner arm 56 fed by gas from control burner 44b and extending around to a point adjacent control burner 21a and'pilot 36. Ignition pilot 53 is also adjacent runner 56. This runner is provided with a series of ports adapted tocarry the flame from'burner 21a around to ignition pilot 53 and to control burner 44?).

In the above assembly it will be seen that various parts have been combined in the unitary structures to make the device more compact.

The constant pilot member 36 is housed in the '-mixing valve 26.

same body member as operating pilot 21a and the ignition pilot operates through the same body member that houses operating pilot 44b. Runner arm 56 is mounted on both the body members of burner 44b and 21a although it will be seen to be out of inner communication with the operating pilot 21a. As has been observed the main body of the device is on the outside of oven wall where, the bi-metal thermostats 33a and 48b are protected from the heat within the oven. Further, the constant pilot and both operating pilots are outside the oven, where they will not afiect the oven thermostat to cause it'to open slightly to admit gas to the main burner, and also where they are not subject to air surges caused by opening the oven door.

The operation of the device is as follows Push button 22 is depressed admitting gas from I manifold 13 to line l6 and thence to T 23. From T 23 it passes simultaneously to constant pilot 36 and operating burner 21a. The way to constant pilot 36 is through line .24, around valve seat 3|, and through 34 and mixing valve 35 to the pilot 36. This is then ignited by hand. The way to operating burner 2la.is by line 25 and The burner 21a immediately lights from constant pilot 36. When this takes place valve 23a is closed against the seat. After operating burner 21a ignites, it heats bi-metal 33a,- and moves valve stem 26a upwardly, as shown in Fig. 1. This then moves valve 29a o'fl seat 30 whence gas flows from manifold I3 through line l5, into chamber 21, around valve seat 30 into line 34, and to constant pilot 36,- so that gas is supplied to theconstant pilot by this line and push button 22 may be released to cut off line |6. Gas from line l5 will likewise flow backwardfrom chamber 21 through line 24 v and line 25 to support operating burner 21a independently of line I6 and the push button. This operation is analogous to an interlock in an elecplace the bi-metal will again cool down so that 2la will reignite. Valve 29a will assume a floating position of equilibrium between seats 30 and 3| so as to leave both open. This is similar to the operation of the .valve disclosed in the patent of Loren F. Doen, Number 1,842,339.

Thus far, they description has been directed to initiating the operation of the device. Usually this will not have to be done, since the constant pilot and operating pilot 21a are designed to'operate at all times. '9

Gas cock I4 is then opened, admitting gas to line 1 and T l8. From T l8 gas flows through line 2| into lower portion C of the valve 20. With bi-metal thermostat 33a heated, passageway 3| will admit a flo-w of gas into passageway 32.

- During the above conditions, section B of valve 20 has been closed and more particularly valve 38b has been seated on 40b. In this condition passageway 4) is in registry with passages 32 and 42, so that gas fiows through passageway 32 to operating burner'44b, and thence torunner arm 56. Simultaneously it flows through by-pass 49 to ignition burner 53. The gas in runner arm 56 is ignited from operating burner 21a or from constant pilot 36, and the flame is transmitted back along the runner by the ports therein. This ignites burner 53 and also burner 44b. When 44b is ignited it heats bi-metal 48b and lifts valve 38b. Gas is then admitted from T |-8 through main burner line .|9, around valve seat 402),

assume an intermediateposition of equilibrium wherein passageway 4") is in partial communication with passageways 32 and 42 so as to provide a reduced quantity ofgas to operate burner 44b and runner arm 56. This position will leave valve 38?) off seat 40b suflicient to admit-ample gas to burner l0. It is of obvious advantage to cut down on runner arm 56 and burner 441) since this reduces the amount of heat onthermostat' 48b'and hence increases its life, and also. prevents waste of gas .by these two burners. ll 0W ever, a full supply of gas is provided to the two burners when they are first ignited and when obviously it s very desirable to have such a large flow.

It will be seen that thermostat 46 may out without affecting the operation of the valve.

When gas cook I4 is closed, the gas supply to.

the main burner is of course out 01!, as also is down on the flow of gas to the main burner the supply of gas to passageway 32 and hence to burners 44b, 53 and runner 56. Burners 21a and 36 will continue to operate unless they are extinguished. Normally the use of push button 22 is necessary only when the device is installed or when the constant pilot has been turned off.

-Should constant pilot 36 and operating pilot 21a become unduly extinguished, bi-metal 3311 will immediately close on seat 30 which cuts off the supply of gas to the constant pilot and also to the operating pilot so that no gas can escape. At the same time passageway 3| will cease to reg ister with passageway 32 and immediately extinguish burners 44b, 53, and 56. Extinguishment of burner Mb permits bi-metal thermostat 48b to cool and seat valve 28b on its seat 4% or out off the supply of gas to the main burner. Thus the entire system is automatically cut out should the constant pilot become extinguished.

Of course, if ignition pilot 53 goes out it will reignite after runner arm 56 is ignited. If this burner 56 becomes extinguished it will reignite after burner 44b is ignited. Should control burner Mb become extinguished bi-metal thermostat 48b will cool and cut off the supply of gas to the main burner. However, this burner should immediately reignite after burners 36 and 21a are ignited.

It will further be observed that bi-metal thenmostat 33a is operable by pilot 36 if desired, and control burner 21a could be eliminated.

It will be seen that an absolutely safe device has been provided. There is no possibility of the escape of any gas since every burner can ignite, directly or indirectly, from the constant pilot or control burner 21a. Should this constant pilot go out, bi-metal thermostat 33a will out off its supply of gas, so that even this quantity will not escape.

The fore oing description refers to elements 26, 35. 43 and 50 as mixing valves. The instant device is particularly concerned with an ignition system for gaseous fuel control and in order to provide a'so-called blue flame at burners 21a, 36. 44b. and 53 it is desirable that the gas supply fluid be mixed with a certain amount of air as is customarily done in the, art to effect such a flame. Therefore, there is included in this description and in the accompanying drawing. the reference to the aforesaid mixing valves (Nos. 26, 35, 43 and 50) without an intent to limit the invention but merely to provide for the inclusion of a well kn wn element.

Furthermore. the constant pilot is outside the oven. It may be properly shielded, and will not be subject to .air surges occasioned by opening the oven door,.which causes some difficulty in systems where the pilot is inside the oven. Also it and the main burner control valve and pilot are located outside the oven. where they do not affect the oven thermostat. The provision of the runner arm transfers the flame into the oven,

in a large flame at flrst,'but after the cycle is in operation. in a very small flame that will not atfect the thermostat. If desirable, the flow of gas to burner 44b may be so regulated that, when it is automatically cut down, only sufllcient gas is available to operate the burner b, and none will traverse the more circuitous pathway into' arm 56. The burner 53 will remain ignited in the oven to furnish a source of ignition for the oven burner. However, it maybe more desirable to supply enough gas to keep runner 56 ignited even when burner 44b is cut down.

1. In combination, a fuel supply, a main burner,-

and an igniter therefor, including a flame pilot spaced from the burner, a first heat operated valve device spaced from said pilot and said burner, a second heat operated valve device adjacent said pilot, each of said devices comprising a valve, thermostatic means for actuating the valve and burner means for affecting the thermostatic means, the burner of said second valve device being connected to said fuel supply and being ignitable from said pilot, means under the control of said second valve device for conducting fuel to the burner of said first valve device, and conducting means for conveying flame from the burner of said second valve device to the burner of said first valve device, and means under the control of said first valve device for conducting fuel to said flame conveying means.

2. Incombination, a fuel supply, a main bumer, and an igniter therefor, including a flame pilot spaced from the burner, a flrst heat operated valve device spaced from said pilot and said burner, a second heat operated valve device adjacent said pilot, each'of said devices comprising a valve, thermostatic means for actuating the valve and burner means for affecting the thermostatic means, the burner of said second valve device being connected to said fuel supply and being ignitable from said pilot, means under the control of said second valve device for conducting fuel to the burner of said first valve device, and conducting means for conveying flame from the burner of said second valve device to the burner of said first valve device, and separate means each under the control of said first valve device for conducting fuel to said main'burner and to said flame conveying means. I

3. In combination, a fuel supply, a main burner, and'an igniter therefor, including a flame pilot spaced from the burner, a first heat operated valve device spaced from said pilot and said burner, a second heat operated valve device adjacent said pilot, each of said devices comprising a valve, thermostatic means for actuating the valve and burner means for affecting the thermostatic means, the burner of said second valve device being connectedto said fuel supply and being ignitable from said pilot, means'under the control of said second valve device for conducting fuel to theburner of said first valve device, conducting means for conveying flame from the burner of said second valve device to the burner of said first valve device, means under the control of said first valve 'device for conducting fuel to said main burner and to said flame conveying means, and said flame conveying means having a part, t m ing into ignitable relation to-said main burner.

4. In combination, a fuel supply, a main burner, and an igniter therefor, including a flame pilot spaced from the burner, a first heat operated valve device spaced from said pilot and said burner, a second heat operated valve device adjacent said pilot, each of said devices comprising a valve, thermostatic means for actuating the valve and burner means for affecting the thermostatic means, the burner of said second valve device being connected to said fuel supply and burner, means under the control of said secondvalve device for conducting fuel to said ignition pilot, meansfor conveying flame from the burner of said second valve device to the burner of said first valve device, and means under the control of said first valve device for conducting fuel to said flame conveying means.

- 5. In combination, a main fuel line, a main .burner in said line, a second fuel line, athermally operated valve in said second line, a primary igniter in said second line and having its fuel supply under the control of said valve, a second thermally operated valve in said mainline controlling the fuel supply to said main burner, each said valves comprising thermostatic means and burner means for affecting the same, means to convey fiame from adjacent the burner of said first valve to the burner of said second valve, and conducting means under the control of said second valve for supplying fuel to said conveying means. I V a k 6. In combination, a main'fuel line, a main burner in said line, a second fuel line, a thermally operated valve in said second line, a prito both said thermally operated valves controlling said conducting means. I I

'7. In combination, a main fuel line, a main burner in'said line, a second fuel line, a thermally operated valve in said second line, a primary igniter in said second line and having its fuel supply under the control of said valve, a

second thermally operated valve in said main line controlling the fuel supply to said main burner,

- each said valves comprising thermostatic means and burner means for affecting the same, means to convey-flame from adjacent the burner of said first valve to the burner of said second valve, and control means in said main fuel line affecting the supply of fuel to said second thermally operated valve and to said conveying means.

8. In combination, a main fuel line, a main burner in said line, 'a second fuel line, a thermally operated valve-in said second line, a primary igniter in said second line'and having its fuel supply under the control of said valve, an ignition burner in said main line and also controlled by said valve, a second thermally operated valve in the main line controlling the fuel supply to said main burner, each of said valves comprising thermostatic valve actuating means and,

burner means for affecting the same, and means conveying flame from adjacent said igniter'to both said ignition burner and the burner means of said second valve.

9.-In combination, a main fuel line, a main burner in said line, a second fuel line, a .thermally operated valve in said second line, a privalve in the main line controlling-thefuel supply to said main hurner, each of said valves comprising thermostatic valve actuating means and burner means for affecting the same, said igniter being directly associated with the burner means for said first valve, means conveying flame from said igniter to both said ignition burner and the burner means of said second valve, and means controlling the fuel supply to said burner means of the second valve, said ignition burner and said conveying means.

10. In combination, a main burner, a fuel supply line, means connected to said line controlling the fuel supply to said burner, a thermal valve in said line, said valve comprising multiple valve means, thermostatic actuating means therefor and burner means for affecting the thermostatic means, a primary igniter in ignitable relation to the valve burner means, fuel conducting means for said valve burner means and said igniter under control of saidvalve, said valve operating to cut off the fuel supply to said igniter and to said valve burner means upon failure of the latter, an ignition burner adjacent said main burner, means to convey flame from adjacent said igniter to said ignition burner, and conducting means also under control of-the multiple valve means of said valve for supplying fuel tosaid ignition burner and to said conveying means.

11. In combination, a primary igniter, a control burner, a thermal valve,- said valve being operated by heat from said control burner, said valve comprising a body having a chamber therein and a pair of fuel passageways leading into said chamber, valve seats defining the inner ends of said passageways and a valve head within said chamber movable between said seats, said head being normally held upon one of said seats and adapted to be moved in response to said heat toward the other of said seats, a fuel supply line connected to the passageway normally closed by said valve head, a fuel line connecting said other passageway and sald control burner, and a fuel line leading from said chamber intermediate said seats to said igniter whereby said valve controls the. supply of fuel to both said igniter and said control valve by means of the head and said first seat and to said control burner alone by means of said head and said second seat.

'BIRCHARD L. MATTHEWS.

JOHN T. MARVIN. 

